dc5850 small form factor psu upgrade help

hello i have a dc5850 small form factor running a 240 wat proprietary i bought a standard 24 pin atx psu from a local computershop and it wouldnt power the mobo after some reasearch i found out that the pinout on my 240 wat psu mobo conector cable is different from a standard atx psu cable is it possible for me to oder a stronger 400watt proprietary psu from hp or from the net that will work on my mobo if not what are my option my geforce210 cant run on my 240watt psu keep in mind my dc5850 Small Form Factor doesnt use a standard atx psu it uses a proprietary atx psu with its own special connector sop what are my options